For the purpose of saving labor, a technology is frequently used to control various processes using image processing in the field of factory automation (FA). A working process of tracking and holding a workpiece using a moving machine (hereinafter referred to as an “industrial robot” or simply as a “robot”) while conveying the workpiece with a conveying device, such as a belt conveyer, can be cited as an example of image processing technology. The working process is called conveyer tracking.
In conveyer tracking technology, an imaging device captures an image of the workpiece on the conveying device. An image processing device then performs measurement processing, such as pattern matching and binarization processing, to the image obtained by the imaging, thereby identifying the position in which each workpiece exists. A robot tracks and holds each workpiece based on the identified position.
For example, in a tracking method disclosed in Patent Document 1 (Japanese Unexamined Patent Publication No. 2002-113679), the images of the plural workpieces conveyed by a conveying body are captured, and handling of the workpieces is controlled based on a position coordinate of each workpiece recognized from the imaging result. More specifically, in a configuration of the tracking method of Patent Document 1, the images of an imaging region of imaging means and a subsequent imaging region are continuously captured within a certain width into which a whole shape of the workpiece fits, while overlapping with each other in the traveling direction. The position coordinate is recognized of only the workpiece including the whole shape in the imaging region.
It is considered that a panoramic image synthesized by utilizing an overlapping portion of the imaging regions is effectively used to look down at the whole state on the conveying route using the continuously-captured images.
Although it is not aimed at the conveyer tracking, Patent Document 2 (Japanese Unexamined Patent Publication No. 5-260264) discloses an image processing device wherein the panoramic image, in the range where an operator captures the images, is generated by joining plural frames, with the operator continuously capturing the images by performing a panning of a hand-held camera.